The future of cancer prevention: setting realistic goals and timeframe Dr Christopher P Wild PhD International Agency for Research on Cancer Lyon, France
We cannot treat our way out of the cancer problem A balanced and integrated approach to prevention, early detection and treatment is required
Cancer control is a complex challenge Because cancer is a highly heterogeneous disease: in occurrence in causes in biology in treatment This calls for national cancer control plans which are integrated with NCD control but reflect national or regional priorities
Cancer control is a dynamic challenge Overall number of cancers is projected to markedly increase, especially in low and middle-income countries The types of cancer which are common change in line with human development (e.g. increases in colorectal and breast and decreases in cervix and stomach)
Primary cancer prevention Around half of cancers could be prevented by applying the knowledge we have; The majority of cancers have a lifestyle or environmental cause, so the potential for prevention is much higher Vineis P and Wild CP (2014) The Lancet, 383: 549-557 See http://www.iarc.fr/
Primary cancer prevention global priorities Risk Factor Comments Tobacco Infections Alcohol Physical inactivity and weight control Implement WHO Framework Convention on Tobacco Control: taxation; bans on advertising; regulation on smoking in public places; counter the introduction into low and middle-income countries HBV and HPV vaccination; H. pylori eradication (?); Avoid contaminated injections; treatment of HBV and HCV chronic carriers increasingly possible Avoid harmful use of alcohol; increase awareness; taxation and regulation Increase physical activity and improve weight control; major area where research is needed to provide evidence-base for preventive interventions
Primary cancer prevention global priorities Risk Factor Radiation Comments Avoid excessive sun exposure and indoor tanning; avoid excessive medical diagnosis, including in children; awareness and remediation of indoor radon levels Environment Occupation Reproductive factors and hormones Healthy diet Address naturally occurring (arsenic, aflatoxins) or man-made (e.g. air pollution) carcinogens through regulatory and other control measures Occupational health; counter risks of exporting at-risk occupational exposures to low and middle-income countries Limit use of HRT; Breastfeeding reduces mother s cancer risk Eat plenty of whole grains, pulses, vegetables and fruits. Limit high-calorie foods; avoid sugary drinks, processed meat; limit red meat and foods high in salt.
Cancers where aetiology is (largely) unknown Organ sites Estimated annual no. new cases worldwide Percent global cancer burden Prostate 1,100,000 7.9 Lymphoma and Leukaemia 850,000 6.0 Kidney 340,000 2.4 Pancreas 340,000 2.4 Thyroid 300,000 2.1 Brain 260,000 1.8 Colorectal 1,400,000 9.7
Two-way Translational Cancer Research Basic Science Population Causes and Preven,on Risk factors Specific molecular altera,ons Prognosis Patient Personalized treatment Laboratory Methodologies genomics, transcriptomics, epigenomics, proteomics, metabolomics Wild CP (2012) Int. J. Epidemiol, 41: 24-32 Wild CP et al., (2013) Env. Molec. Mutagen.54: 480-499
Cancer causation clues from genomics (Scelo et al., Nature Comm. 5: 5135, 2014) Mutation patterns from WGS of 95 conventional renal cell cancers: High A>T mutation rates in Romanian cases Mutation distributions: A>C G>C A>G G>T A>T G>A Romania Czech Rep. (N=29) Russia (N=23) UK (N=29) (N=14) EC FP7 programme Typical signature of Aristolochic acid induced mutations: Known in TP53 for rare urothelial cancers Established genome wide in mouse fibroblasts First study to implicate an unanticipated environmental factor through analysis of genomic data Major potential for disease prevention
Secondary prevention global priorities Breast cancer*: mammography; clinical breast examination; breast awareness Cervical cancer: cytology; HPV DNA testing; visual inspection with acetic acid Colorectal cancer: FOBT, sigmoidoscopy, colonoscopy Oral cancer: visual inspection; in high incidence regions (e.g. east Asia) among high risk groups The prime importance of quality-assured, national programmes *IARC Handbook on Cancer Prevention vol. 15 Nov 2014; supported by INCa, France
Prevention works but takes time lung and cervix Lung, men Cervix uteri
The need for implementation research Moving from the demonstration of efficacy in trials to effectiveness in programmes Integrating research and health services development building-in capacity
Research funding the need for a different model Research on prevention is under-funded (2-3% in Australia, Canada and UK), yet vital to cancer control Relatively little private sector interest in prevention research Governments need independent, policy-relevant research (e.g. on diet) Public research funding needs to be directed to prevention, otherwise knowledge gaps will remain An international research coordination is required
We have a duty of care to the patients of today and to the populations of tomorrow